* while {@code ImmutableSortedSet.of(s)} returns an {@code ImmutableSortedSet<Set<String>>}
   * containing one element (the given set itself).
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is
   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *

   * while {@code ImmutableSortedSet.of(s)} returns an {@code ImmutableSortedSet<Set<String>>}
   * containing one element (the given set itself).
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is
   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *

              && ((RegularImmutableSortedSet) result).isSubset;
      if (!isSubset) {
        // Only return the original copy if this immutable sorted set isn't
        // a subset of another, to avoid memory leak.
        return result;
      }
    }
    return copyOfInternal(comparator, elements.iterator());
  }

  private static <E> ImmutableSortedSet<E> copyOfInternal(